1. Field of the Invention
The present invention relates to an image forming apparatus provided with a user authentication function for controlling approval and disapproval of an operation on print data.
2. Description of the Related Art
When document data is transmitted from a personal computer (PC) to an image forming apparatus and then is printed, the document data is transformed into a page description language (PDL) document with a desired print layout by use of a printer driver installed in the PC; and then the created PDL document is transmitted to and printed by the image forming apparatus. Meanwhile, there is also an image forming apparatus configured to receive document data in the portable document format (PDF) and the like that are widely used in the PC environment; then to convert the received document data into a printable format; and to execute a printing process. Further, there is also an image forming apparatus configured to convert document data received from a PC into a printable format; to temporarily store the converted document data in an auxiliary storage device inside the image forming device; and to render the data printable at a desired timing.
Some document data can accept various password settings. For example, a PDF document can accept a password setting such as a “password for opening a document,” an “authority password” or a “password for opening an attached file.” If the “password for opening a document” is set to request a user to input the password before opening the PDF document, only a user authorized in advance is allowed to open the file, and thus access to the document for preview is controlled. Meanwhile, if the “authority password” is set, access to the document for printing and editing is controlled. Further, if the “password for opening an attached file” is set, access to the file attached to the document is controlled.
Upon receipt of the document data provided with such access control (password-protected document data) from the PC, the image forming apparatus converts the document data into the printable format and saves the document data in its storage device as password-protected print data. When a user wishes to access the saved print data, the image forming apparatus requests the user to input the password. However, if a user is requested to input a password in every operation using a touch panel or various buttons on the image forming apparatus, the user is annoyed by such password input. To address this problem, Japanese Patent Laid-Open No. 2007-237685 discloses an image forming apparatus which functions in collaboration with an authentication system, and allows users to access print data without requesting password inputs. In this image forming apparatus, a “document creator” and “accessible users and their authorities” for a document are managed as document information that is associated with print data. Thereby, when a user of the image forming apparatus is either the “document creator” or the “accessible user,” the user is allowed to access the print data without inputting the password.
The apparatus according to Japanese Patent Laid-Open No. 2007-237685 allows users authorized in advance (either as the “document creator” or the “accessible user”) to access the print data without inputting the password even in the case where the print data is password-protected print data. However, a user who knows the password but is not authorized in advance has to input the password every time the user wishes to access the print data. Moreover, the apparatus according to Japanese Patent Laid-Open No. 2007-237685 unconditionally allows the users once authorized in advance to access print data even after the password for the print data is changed. Therefore, this apparatus has a problem that its security level is low.